This subcontract is part of a five-year project that proposes to link records from the 1940 U.S. Census to participant data from five ongoing national longitudinal studies: Wisconsin Longitudinal Study (WLS), Panel Study of Income Dynamics (PSID), Health and Retirement Study (HRS), National Social Life, Health and Aging Project (NSHAP), and National Health and Aging Trends Study (NHATS). The primary objective of the project is to supplement the data available in these studies with rich information on early life social, economic, family, neighborhood, and environmental circumstances and make these data available to the research community. The proposed project is based at the University of Minnesota (Rob Warren, PI) and includes Co-Investigators at the University of Wisconsin, University of Chicago, Westat, and the University of Michigan. The preliminary work of assembling data extracts containing individual identifiers that will be used to link PSID and HRS participants to their Census 1940 record and the actual linkage of participants for these two studies will occur at the University of Michigan. Preparation and dissemination of data files and documentation for the linked Census data for PSID and HRS will also take place at Michigan.